Binaural and top-down mechanisms in auditory scene analysis

摘要 在我们平时忙碌的生活中，我们很少听到孤立的声音。在大多数情况下，如鸡尾酒会，许多人 声源是存在的，它们的波形在听众的耳朵里简单地相加；所有的听众 HEAR是一个单一的复杂波形。值得注意的是，听众能够分解这种复杂的波形， 根据频率和其他提示将这些成分分开，并将它们组合在一起以形成一致的感知 这一过程通常被称为“听觉场景分析”。助听器和 人工耳蜗使用者在这个过程中有特别的困难，许多人避免在多个环境中 存在声源。更好地理解听觉场景分析背后的机制可能会 解决其中的一些困难。听觉场景分析是利用声音的特征进行分析的过程 (自下而上处理)和监听者的期望(自上而下处理)。的长期目标是 建议的研究是为了了解自下而上加工的机制以及它是如何与 自上而下的处理。 这项拟议的研究旨在了解用于提取单个耳鸣的双耳机制的生理学。 来自具有多个声源的环境的声音。听觉系统可以比较和对比 两只耳朵的输入，并使用这些双耳提示来分离声音。人们对此知之甚少 当存在多种声音时，比较两只耳朵的输入的生理过程。这种缺乏 知识已成为进一步提高戴助听器或人工耳蜗者听力的障碍 在两只耳朵里植入。这项拟议研究的目的之一是确定在 当存在多个声源时提取单个声音。本提案将使用多个 复杂声音(谐音复合体)，用于识别用于分离声音的双耳神经机制。 拟议研究的第二个目标是确定自上而下的过程如何影响双耳 用于分离声音的机制。这项拟议的研究将结合电生理学在亚 用听皮层失活技术确定双耳之间的相互作用 机制和自上而下的处理。这些结果将为双耳优势提供一个框架 可能有助于最大限度地利用双边助听器和双边 植入人工耳蜗术。

ABSTRACT In our normal busy lives we rarely hear isolated sounds. In most situations, such as a cocktail party, many sound sources are present and their waveforms simply add together at the listener's ears; all that listeners hear is a single complex waveform. Remarkably, listeners are able to break down this complex waveform, segregate the components by frequency and other cues, and group them together to form a coherent percept of the separate sources; this process is commonly referred to as "auditory scene analysis". Hearing aid and cochlear implant users have particular difficulty with this process and many avoid environments where multiple sound sources are present. A better understanding of the mechanisms underlying auditory scene analysis may solve some of these difficulties. Auditory scene analysis is a process that utilizes the features of the sound (bottom-up processing) and the expectations of the listener (top-down processing). The long-term objective of the proposed research is to understand the mechanisms of the bottom-up processing and how it interacts with the top-down processing. The proposed research aims to understand the physiology of the binaural mechanisms used to extract a single sound from an environment with multiple sound sources. The auditory system can compare and contrast the input of the two ears and use these binaural cues to segregate sounds. Little is understood about the physiological processes that compare the input of the two ears when multiple sounds are present. This lack of knowledge has become a barrier to further improving the hearing of people with hearing aids or cochlear implants in both ears. One aim of the proposed research is to determine the binaural mechanisms used in extracting a single sound when multiple sound sources are present. The present proposal will use multiple complex sounds (harmonic complexes) to identify the binaural neural mechanisms used to segregate sounds. The second aim of the proposed research is to determine how top-down processes affect the binaural mechanisms used to segregate sounds. The proposed research will combine electrophysiology in the inferior colliculus with auditory cortical inactivation techniques to determine the interaction between binaural mechanisms and top-down processing. The results will provide a framework for binaural advantages in complex environments that may help with maximizing the benefit from bilateral hearing aids and bilateral cochlear implants.